[Influence of implant restoration on traditional restoration idea].

Implant restoration affected the traditional restoration idea. Artificial implant restoration has a profound influence on the design of dental restoration. Implant supported prostheses have not only changed the method of oral rehabilitation, but also integrated revolutionary concept with the traditional treatment protocol. By using implants, posterior missing molars can be effectively restored and thus eliminating the disadvantages of traditional removable partial denture for Kennedy classification Ⅰ, Ⅱ partically edentulous dentition. Full edentulous arch can also be restored with implant fixed denture which provide much better oral health related quality of life compared with the traditional complete denture. It is useful to master the theory and skills of artificial implant restoration, and to provide a reference for the restoration of oral physiological function.

Theoretical role of adjunctive implant positional support in stress distribution of distal-extension mandibular removable partial dentures.

This preliminary study evaluated the adjunctive supporting role of diverse implant positions on stress distribution in a Class I removable partial denture (RPD) design. Nine three-dimensional finite element models were prepared to simulate mandibular RPD designs with three different loading conditions applied. Implant supported designs demonstrated lower stress value concentrations and mucosal displacement.

Partial Edentulism based on Kennedy's classifcation: an epidemiological study.

BACKGROUND: The aim of this study was to determine the incidence of different Kennedy's classes of partial edentulism during 18 months period. MATERIALS AND METHODS: Patients were clinically examined for various Kennedy's classes of partial edentulism in the outpatient department (OPD), prosthodontics, GPRDCH, Kurnool (Andhra Pradesh). RESULTS: Of the total 1,420 OPD patients, Kennedy's class III was the most frequent classification encountered (62%) and followed by Kennedy's class I (18%), class II (11%), and class IV (9%) in decreasing order. CONCLUSION: The patients with various Kennedy's classes of partial edentulism can be offered various treatment modalities like removable cast partial dentures, fixed partial dentures, over dentures and implant supported dentures. This study can be crucial for screening the population for incidence of tooth loss as a factor of gender and age. Clinical significance: Tooth loss appears to have an important role in the loss of esthetics and mastication. Study of incidence of various classes of partial edentulism provides clinically useful information for dental training and continuing education.

Intracoronal mandibular Kennedy Class I implant-tooth supported removable partial overdenture: a 2-year multicenter prospective study.

PURPOSE: The aim of this study was to assess the clinical status and radiographic and densitometric peri-implant tissue changes as parameters for the success or failure of 40 mandibular implants supporting intracoronal mandibular Kennedy Class I removable partial overdentures in a 2-year prospective study. MATERIALS AND METHODS: Twenty consecutively treated men who received mandibular implants bilaterally to support an intracoronal Kennedy Class I removable partial overdenture were selected. Plaque and gingival bleeding indices, probing pocket depths, marginal bone loss, and bone mineral density were recorded. Bone loss and density were assessed through intraoral periapical radiographs and dual-energy x-ray absorptiometry, respectively. Data were recorded at the time of overdenture insertion and 6, 12, 18, and 24 months later. RESULTS: Two implants failed, resulting in a success rate of 95% after 24 months. The plaque and gingival bleeding indices changed significantly between the different observational periods. Within the physiologic limit, there were detrimental effects on both marginal bone levels and probing pocket depths. Meanwhile, the bone mineral density around the implants increased significantly in a time-dependent manner. CONCLUSION: Within the limitations of this study, mandibular implants supporting an intracoronal Kennedy Class I removable partial overdenture can be recommended as a viable treatment modality for rehabilitation of patients with partial bilateral mandibular posterior edentulism.

Case-control study on the survival of abutment teeth of partially dentate patients.

OBJECTIVES: Due to the scarce amount of data available, a retrospective analysis of patients treated with removable dental prostheses (RDPs) was performed. The aim of the trial was to evaluate the rate of repairs and failures of attachment-retained RDPs (AR-RDPs) compared to clasp-retained RDPs (CR-RDPs) with respect to cofactors (e.g., type of loading). In this respect, two hypotheses were proposed: AR-RDPs are more prone to repairs than CR-RDPs, and AR-RDPs are more prone to fail than CR-RDPs. MATERIALS AND METHOD: Two hundred three patients treated with 135 AR-RDPs and 68 CR-RDPs between 1994 and 2006 were evaluated in this trial. The dental treatment was carried out in the clinical training course of senior students. Kaplan-Meier estimates were calculated for the primary end point (repairs) and for the secondary end point (failures). RESULTS: The survival of CR-RDPs and AR-RDPs did show significant differences regarding repairs (p = 0.034) but not with regard to failures (p = 0.169). Prostheses of the non-axially loaded group showed no significant differences in the frequency of repairs and failures. CONCLUSIONS: Technical complications occurred more frequently in the CR-RDP group. Taking the higher observation time in the AR-RDP group into account, CR-RDPs are more prone to repairs, especially to those with technical background (e.g., fracture of the metal framework). CLINICAL RELEVANCE: The use of crowns with rod attachments on tilted teeth seems to be an appropriate treatment approach in order to simplify removable dental prosthesis design.

Survey of partial removable dental prosthesis (partial RDP) types in a distinct patient population.

STATEMENT OF PROBLEM: Current demographic information on the number and types of removable partial dentures is lacking in the prosthodontic literature. PURPOSE: This study was designed to investigate patterns of tooth loss in patients receiving removable partial dentures (RPDs) in eastern Wisconsin. MATERIAL AND METHODS: Digital images (1502) of casts at 5 dental laboratories in eastern Wisconsin were collected. Any prescription requesting fabrication of a removable partial denture was photographed twice. The first photograph was made immediately upon arrival at the laboratory, while the second photograph was made immediately before being returned to the prescribing dentist for the first time. A calibrated investigator analyzed all the photographs for Kennedy Classification, type of RPD, major connector, and other details. Data were analyzed with descriptive statistics. Fisher's exact test was used to confirm repeatability. RESULTS: Kennedy Class I was the most common RPD with a frequency of 38.4%. More than 40% of prescriptions had no design input from the dentist. One in 3 RPDs used acrylic resin or flexible frameworks. One in 5 RPDs had no rests. The horseshoe major connector was the most common maxillary major connector, while the lingual plate was the most common in the mandible. CONCLUSIONS: RPDs remain a common prosthodontic treatment in this region. Non-metal RPD frameworks are a common treatment type and rarely include rests. These data indicate a changing partially edentulous patient population and a variable commitment to standard levels of prosthodontic care.

Partial edentulism and removable partial denture design in a dental school population: a survey in Greece.

OBJECTIVES: To investigate the pattern of partial edentulism and the most frequent designs of cobalt-chromium removable partial dentures (RPDs), constructed at the Dental School of Athens, Greece. METHODS AND MATERIALS: Five hundred and fifty-three patients, between 42 and 81 years old, mostly males, treated by undergraduate dental students, were included. The survey was based on visual evaluation of master casts and work authorisation to dental technicians. Aspects examined were: Kennedy Classification, modification areas, major connectors, clasping, placement of rest seats and indirect retention. RESULTS: Kennedy Class I was the most common encountered in the maxilla (50.5%) and in the mandible (70%). The most frequent major connectors were the lingual bar (92.6%) and the U-shaped palatal strap (54%). The most common clasp was the Roach (69.2%) in Class I and Class II. In Class III and IV, the most common was the occlusally approaching clasp (55% and 70%). The most frequent location of the rest was mesial of abutment teeth. On the average, 39.5% of Class I RPDs and 58.6% of Class II RPDs had indirect retainers. CONCLUSION: A combination of the two major philosophies of RPD design (biomechanical and hygienic) was evident in the RPDs examined in our study.

ICK classification system for partially edentulous arches.

Several methods of classification of partially edentulous arches have been proposed and are in use. The most familiar classifications are those originally proposed by Kennedy, Cummer, and Bailyn. None of these classification systems include implants, simply because most of them were proposed before implants became widely accepted. At this time, there is no classification system for partially edentulous arches incorporating implants placed or to be placed in the edentulous spaces for a removable partial denture (RPD). This article proposes a simple classification system for partially edentulous arches with implants based on the Kennedy classification system, with modification, to be used for RPDs. It incorporates the number and positions of implants placed or to be placed in the edentulous areas. A different name, Implant-Corrected Kennedy (ICK) Classification System, is given to the new classification system to be differentiated from other partially edentulous arch classification systems.

Long-term analysis of telescopic crown retained removable partial dentures: survival and need for maintenance.

OBJECTIVES: The aim of this retrospective longitudinal study was to evaluate the clinical long-term survival of telescopic crown retained removable partial dentures (TRPDs), the influencing factors on survival as well as the type and number of necessary treatments during the observation time. METHODS: The study is based on the data of 463 patients who had received a total of 554 TRPDs with a total of 1758 telescopic crowns between 1995 and 2004 in our Dental School. The influence of the patient's gender, location of the denture, number of abutment teeth per telescopic denture, their distribution (Kennedy-class) and the impact of a routinely follow-up programme on the survival probability were analysed. RESULTS: During the observation period (mean 5.3+/-2.9 years) 4.7% of the TRPDs ceased functioning and 3.8% of the abutment teeth were extracted. The survival probability after 5 years was 95.1% for the TRPDs and 95.3% for the abutment teeth. No denture with more than four abutments required replacement. Only the covariates number of abutment teeth and patient in-follow-up showed a significant (p<0.01) influence on the survival probability. 26.9% of the TRPDs needed facing repairs, 34.8% relines, 20.6% loss of cementation of a primary crown and 1% abutment tooth treatment. CONCLUSIONS: Within the limits of a retrospective study it can be concluded that the number of attachments and thorough aftercare have a considerable impact on the long-term success of TRPDs. Though loss of cementation and defects of the facings were significant in number, they did not endanger the long-term success of a TRPD at all.

Rotational path removable partial denture: an esthetic alternative.

Missing teeth can be replaced using any of a number of methods. Patients may choose to replace missing teeth with a prosthesis that is either removable, fixed, or retained with implants. When it is necessary to replace anterior or posterior teeth, a properly designed and fabricated rotational path removable partial denture can be both successful and esthetically pleasing to the patient. However, while a patient's functional and esthetic needs can be met successfully, rotational path removable partial dentures can be more demanding for the laboratory technician to fabricate and for the dentist to seat in the mouth. Rotational path removable partial dentures frequently are overlooked as a viable means of treating missing teeth. This article reviews the principles of rotational path removable partial dentures, as well as their categories, advantages, and disadvantages, in the hope that more dentists will consider them when the need arises.

Indications for removable partial dentures: a literature review.

PURPOSE: The purpose of this report was to evaluate indications for the use of removable partial dentures based on a comprehensive literature review. MATERIALS AND METHODS: Using a model similar to a Delphi process, the literature relating to the indications and contraindications for the prescription of removable partial dentures was discussed by seven experienced educators in a 2.5-day workshop. RESULTS: Evidence for indications and contraindications for the prescription of removable partial dentures is not clearly stated in the literature; however, some basic principles are defined. There appears to be a trend in favor of the use of the shortened dental arch concept or implant-supported restorations instead of conventional removable partial dentures, given the evidence that the long-term use of removable dentures is associated with increased risks of caries and periodontitis and low patient acceptance. The presence of sound abutment teeth appears to encourage the use of removable partial dentures, as the fixed partial denture alternative requires sacrifice of healthy hard tissues. When economic factors influence the decision-making process, removable partial dentures are often chosen. CONCLUSION: While evidence-based indications and contraindications for prescribing removable partial dentures are still lacking, major underlying principles for clinical decision making are identified.

Prevalência de arcadas parcialmente desdentadas, segundo a classificação de Kennedy, na cidade de Goiânia - GO / Prevalence of partially edentulous arches, according to Kennedy classification, in Goiania city - GO

O objetivo deste estudo foi verificar topograficamente a prevalência de espaços protéticos em arcadas parcialmente desdentadas, registradas em prontuários clínicos da Faculdade de Odontologia da Universidade Federal de Goiás, no período de 1983 a 1993. Os resultados evidenciaram um total de 1976 pacientes durante o período de avaliação, sendo 73,5% do sexo feminino e 26,5% do sexo masculino; 57,9% das próteses foram mandibulares e 42,1% delas, confeccionadas na maxila. Houve uma prevalência de 46,9% de arcadas do tipo classe III; 25,4% de classe I; 23,2% de classe II e apenas 4,5% de arcadas desdentadas foram do tipo classe IV

A clinical overview of removable prostheses: 2. Impression making for partial dentures.

This, the second article in a series on the prescription of removable partial dentures, will deal with the issue of primary impression and primary casts for partial dentures. The principles of definitive impressions and master cast planning will be described.

Removable partial denture design: a study of a selected population in Saudi Arabia.

Determination of the incidence of various classes of removable partial dentures (RPDs) including their designs and their comparison with previous studies provide clinically useful information for dental training and continuing education. The purpose of this study is to determine the pattern of partial edentulism, the major connector, clasping, and design of 740 cobalt chromium RPD frameworks constructed for a selected population in Saudi Arabia. RPD framework design information and patient personal data were obtained from the work authorization form and the dental records respectively. The relationship among age, sex, nationality, and various Kennedy classes of the RPDs was determined by chi-square statistical analysis. Results indicate that Kennedy Class III removable partial dentures were the most frequently constructed. Although gender had no significant relationship, age and nationality had statistically significant relationship with the distribution of various Kennedy classes of removable partial dentures. Lingual bars and anterior posterior palatal straps were the most commonly used mandibular and maxillary major connectors. Lingual and palatal plates, however, were more frequently used than any major connectors for distal extension RPDs. Comparison with previous findings confirms the established variation in designing RPDs. The distribution of partially edentulousness revealed the influence of the general pattern of tooth loss, which could be modified by patient's demands and socio-economic status. Practitioners need to avail themselves fully of basic RPD design principles concerning the most commonly encountered classes of RPDs.

Quality of removable partial dentures worn by the adult U.S. population.

STATEMENT OF PROBLEMS: Research-based assessments of the quality of removable partial dentures (RPDs), especially within a large patient population, are lacking. PURPOSE: This study evaluated the prevalence and quality of RPDs by use of the National Health and Nutrition Survey (NHANES III) data set. MATERIAL AND METHODS: Estimates of the health and nutritional status of the American population were obtained from the NHANES III data set (1988-1994). Calibrated dentists performed dental examinations on 17,884 adults. If the subject wore an RPD, its quality was assessed with 5 criteria: integrity, tooth wear, the presence of temporary reline material or adhesive, stability, and retention. In this study, the data on RPD defects were used to assess the prevalence of problems. The original population was divided into 4 subgroups: paired RPD data = subjects wearing both maxillary and mandibular RPDs (n = 600 prostheses, 300 maxillary and 300 mandibular); single RPD data = subjects with only one RPD (n = 1003 prostheses, 511 maxillary and 492 mandibular); maxillary versus mandibular RPD data = all subjects with all RPDs (n = 1603 prostheses, 811 maxillary and 792 mandibular); and pooled RPD data = all subjects with a single RPD plus subjects with 2 RPDs, counting only the RPD with the most defects (n = 1303 prostheses, 674 maxillary and 629 mandibular). The subjects were analyzed with descriptive statistics. The distribution of defects in the RPDs was examined for possible associations with chi(2) tests. The paired data for patients with both maxillary and mandibular RPDs were analyzed with Wilcoxon signed rank tests. The prevalence of RPDs as a function of patient age and the association between RPD defects and patient age were analyzed with chi(2) tests. The results were considered highly significant at P<.0001 and significant at P<.05. RESULTS: Of the 17,884 adults who underwent a dental examination, 1306 had RPDs. Three patients were excluded because their records were incomplete, leaving 1303 patients available for analysis. Most of the prostheses examined (65%) had at least 1 defect. Lack of stability was the most prevalent single defect. Distinctions in the type and prevalence of defects were observed between mandibular and maxillary RPDs. Mandibular RPDs had significantly more problems related to retention, whereas maxillary RPDs had significantly more problems related to the presence of reline material and to integrity defects. Tooth wear defects were significantly associated with patient age (P<.0001). Only one third of the RPDs were considered satisfactory according to NHANES III criteria. CONCLUSION: A review of the database used in this study indicated that, in spite of a decline in tooth loss, RPDs are still used in all age cohorts, including young adults. A large number of RPDs were found to have defects.

A clinical overview of removable prostheses: 3. Principles of design for removable partial dentures.

Removable partial dentures (RPDs) should not be made for patients unless they are necessary. Most partial dentures have the potential to cause some damage to the teeth and supporting tissues, however well they are designed and constructed; the criteria for selecting such devices were described in a previous article. In general there is merit in, wherever possible, reducing tissue coverage as much as possible when RPDs are being planned. This article, the third in a series on the prescription of RPDs, discusses the design principles involved.

Treatment outcomes with removable partial dentures: a comparison between patient and prosthodontist assessments.

PURPOSE: This article presents the results from a survey of patients' degree of satisfaction with their removable partial dentures (RPD) and the comparison between patient and prosthodontist assessments. MATERIALS AND METHODS: A total of 165 experienced RPD wearers filled in a questionnaire and graded their RPDs depending on their level of satisfaction. A scale ranging from 1 to 5 was used to assess general satisfaction with RPDs and to assess their esthetics, retention, and hygiene. A specialist in prosthodontics assessed the same prostheses using the same scale, not knowing the patient's opinion. RESULTS: The patients' assessments were high, and more than half of them graded their dentures as excellent. On average, all variables were assessed higher by the patients than by the prosthodontist (P < .001). For the patients who gave the worst grades to their dentures, the grades were lower than the prosthodontist's (P < .001), while the satisfied patients graded their dentures much better than did the prosthodontist (P < .001). CONCLUSION: On average, patient assessment of the treatment outcomes with RPDs was less critical than prosthodontist assessment. However, the few dissatisfied patients assessed their dentures worse than did the prosthodontist.